For one sprinklers should be used at night or late evening if you do during the day you will lose too much water due to evaporation plus on sunny days you risk damage to your lawn because water droplets act like tiny magnifying glasses and can overheat the blades of grass.
Secondly you were parked on his side if the street in front of his house. It's your fault if he wanted to turn HIS sprinklers on. Get over it or just buy a all weather car cover.
Cancer's a bitch! Enjoy life while you can! LIVE, LOVE, DRIVE...CAMARO!
The Bird is the word!